AU609969B2 - Method of preparing lactulose - Google Patents
Method of preparing lactulose Download PDFInfo
- Publication number
- AU609969B2 AU609969B2 AU33391/89A AU3339189A AU609969B2 AU 609969 B2 AU609969 B2 AU 609969B2 AU 33391/89 A AU33391/89 A AU 33391/89A AU 3339189 A AU3339189 A AU 3339189A AU 609969 B2 AU609969 B2 AU 609969B2
- Authority
- AU
- Australia
- Prior art keywords
- isomerisation
- lactose
- lactulose
- hydrogen peroxide
- basic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000000034 method Methods 0.000 title claims abstract description 22
- JCQLYHFGKNRPGE-FCVZTGTOSA-N lactulose Chemical compound OC[C@H]1O[C@](O)(CO)[C@@H](O)[C@@H]1O[C@H]1[C@H](O)[C@@H](O)[C@@H](O)[C@@H](CO)O1 JCQLYHFGKNRPGE-FCVZTGTOSA-N 0.000 title claims abstract description 15
- 229960000511 lactulose Drugs 0.000 title claims abstract description 15
- PFCRQPBOOFTZGQ-UHFFFAOYSA-N lactulose keto form Natural products OCC(=O)C(O)C(C(O)CO)OC1OC(CO)C(O)C(O)C1O PFCRQPBOOFTZGQ-UHFFFAOYSA-N 0.000 title claims abstract description 15
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 26
- 238000006317 isomerization reaction Methods 0.000 claims abstract description 21
- GUBGYTABKSRVRQ-QKKXKWKRSA-N Lactose Natural products OC[C@H]1O[C@@H](O[C@H]2[C@H](O)[C@@H](O)C(O)O[C@@H]2CO)[C@H](O)[C@@H](O)[C@H]1O GUBGYTABKSRVRQ-QKKXKWKRSA-N 0.000 claims abstract description 14
- 239000008101 lactose Substances 0.000 claims abstract description 14
- 239000011541 reaction mixture Substances 0.000 claims abstract description 5
- UKLNMMHNWFDKNT-UHFFFAOYSA-M sodium chlorite Chemical compound [Na+].[O-]Cl=O UKLNMMHNWFDKNT-UHFFFAOYSA-M 0.000 claims abstract description 5
- 229960002218 sodium chlorite Drugs 0.000 claims abstract description 5
- 238000011160 research Methods 0.000 claims description 2
- MLGCXEBRWGEOQX-UHFFFAOYSA-N tetradifon Chemical compound C1=CC(Cl)=CC=C1S(=O)(=O)C1=CC(Cl)=C(Cl)C=C1Cl MLGCXEBRWGEOQX-UHFFFAOYSA-N 0.000 claims description 2
- 239000000825 pharmaceutical preparation Substances 0.000 abstract 1
- 229940127557 pharmaceutical product Drugs 0.000 abstract 1
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 16
- 239000002253 acid Substances 0.000 description 7
- 239000011734 sodium Substances 0.000 description 7
- 150000007513 acids Chemical class 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- 238000000354 decomposition reaction Methods 0.000 description 5
- 238000002474 experimental method Methods 0.000 description 5
- 150000002500 ions Chemical class 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 239000007800 oxidant agent Substances 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- DWAQJAXMDSEUJJ-UHFFFAOYSA-M Sodium bisulfite Chemical compound [Na+].OS([O-])=O DWAQJAXMDSEUJJ-UHFFFAOYSA-M 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 235000010267 sodium hydrogen sulphite Nutrition 0.000 description 2
- 239000004289 sodium hydrogen sulphite Substances 0.000 description 2
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 description 2
- -1 sulphite ion Chemical class 0.000 description 2
- NCPXQVVMIXIKTN-UHFFFAOYSA-N trisodium;phosphite Chemical compound [Na+].[Na+].[Na+].[O-]P([O-])[O-] NCPXQVVMIXIKTN-UHFFFAOYSA-N 0.000 description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 229910001919 chlorite Inorganic materials 0.000 description 1
- 229910052619 chlorite group Inorganic materials 0.000 description 1
- QBWCMBCROVPCKQ-UHFFFAOYSA-N chlorous acid Chemical compound OCl=O QBWCMBCROVPCKQ-UHFFFAOYSA-N 0.000 description 1
- 238000004040 coloring Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- AQSJGOWTSHOLKH-UHFFFAOYSA-N phosphite(3-) Chemical compound [O-]P([O-])[O-] AQSJGOWTSHOLKH-UHFFFAOYSA-N 0.000 description 1
- 150000003009 phosphonic acids Chemical class 0.000 description 1
- OJMIONKXNSYLSR-UHFFFAOYSA-N phosphorous acid Chemical compound OP(O)O OJMIONKXNSYLSR-UHFFFAOYSA-N 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 description 1
- 235000010265 sodium sulphite Nutrition 0.000 description 1
- RBWSWDPRDBEWCR-RKJRWTFHSA-N sodium;(2r)-2-[(2r)-3,4-dihydroxy-5-oxo-2h-furan-2-yl]-2-hydroxyethanolate Chemical compound [Na+].[O-]C[C@@H](O)[C@H]1OC(=O)C(O)=C1O RBWSWDPRDBEWCR-RKJRWTFHSA-N 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
- C07H3/00—Compounds containing only hydrogen atoms and saccharide radicals having only carbon, hydrogen, and oxygen atoms
- C07H3/04—Disaccharides
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Biochemistry (AREA)
- Biotechnology (AREA)
- General Health & Medical Sciences (AREA)
- Genetics & Genomics (AREA)
- Molecular Biology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Saccharide Compounds (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Medicinal Preparation (AREA)
Abstract
The invention relates to a new method of preparing lactulose by basic isomerisation of lactose. According to the invention the reaction mixture is treated with hydrogen peroxide or sodium chlorite to obtain lactulose of an acceptable colour for a pharmaceutical product. Preferably 0.5 - 5 g of hydrogen peroxide are used per kg of lactose. 1H2O.
Description
AUSTRALIA
Patents Act COMPLETE SPECIFICATICtN
(ORIGINAL)
Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority This document cnan h Related Art: Earnendrnts made tinder 0 00Section 49 and is correct for ~p 1rinting.
APPLICANT'S REFERE29E: DIR 0414A/M/JNK 'Name(s) of Applicant(s): Duphar International Research B.V Address(es) of Applicant(s): C.J. van I-outenlaan 36, Weesp, THE NETHERLANDS.
Address for Service is: I: PHILLIPS OR4CN>DE FITZPATRI1CK Patent and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Complete Specification for the invention entitled: METHOD OF PRPAM11rG LACThLOSE Our Ref 128240 POF Code: 1596/463997 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): 6003q/1 -1- PHILLIPS ORMONDE AND FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne, Australia P17/1179 STUART TAYLOR la DIR 0414 Method of preparing lactulose The invention relates to a new method of preparing lactulose by basic isomerisation of lactose.
A conventional method of preparing lactulose from lactose comprises the basic isomerisation of lactose at elevated temperature. During the said isomerisation reaction are formed in addition to lactulose decomposition products thereof, and a brown-coloured reaction mixture is obtained.
It is known that the brown colouring of the mixture during the isomerisation can be mitigated by carrying out the isomerisation in the presence of sodium sulphite, sodium bisulphite or sodium phosphite. It is assumed that the sulphite ion, bisulphite ion or phosphite ion reacts with the decomposition products of lactulose while forming 4 t€ sugar sulphonic acids and sugar phosphonic acids which can then be removed by means of ion exchangers.
Such a method is known from Netherlands Patent Specification no. 165467 in which the use of sodium sa o sulphite, from United States Patent Specification no.
4,536,221 in which the use of sodium bisulphite, and from Netherlands Patent Application No. 7907259 in which the use 00oo 25 of sodium phosphite as an oxidant is described. However, the formed sugar sulphonic acids and sugar ph sphonic acids are hard to decompose on purifying the waste water in a t oO water treatment plant and hence they are ecologically S°,g unsound.
It has now been found that such problems do not i present themselves when hydrogen peroxide or sodium chlorite is used in the method mentioned in the preamble instead of sulphite, bisulphite or phosphite.
Hydrogen peroxide both in an acid medium and in a basic medium may serve as an oxidant and consequently can -iboxidize the decomposition products of lactulose which are formed during the isomerisation to (carboxylic) acids which can be removed by means of ion exchangers.
Excellent results are also obtained with sodium chlorite as a coreagent besides the sodium hydroxide required for the isomerisation, but as a result of the formation of corrosive compounds, for example, chlorine and chlorodioxide, during the reaction, higher requirements are imposed on the apparatus than when hydrogen peroxide is used.
Therefore according to the present invention there is provided a method of preparing lactulose by basic isomerisation of lactose, wherein the reaction mixture is treated with hydrogen peroxide or sodium chlorite.
According to a preferred embodiment of the method according to the invention hydrogen peroxide is used as an oxidant and is added after the basic isomerisation reaction of 0 0 0o lactose to lactulose. Preferably 0.5-5 g of hydrogen peroxide oo is used per kg of lactose.1H 0.
0 0 0 0 0 00 0o 00 0 0 0 0 0 0 0 00 00 0 0 0 0 o o 00 00 0 0 0 0 0 0 0 i 000000 0 0 0000ooo o 00 0 00 0 0 00 0 00o 0 00 0 0 0 0 0 00 0 o 000000 0 0 S MW/2320U
L-
DIR 0414 oxidize thed CO0 mpo Siti on products. of l-a tuose which- are formed during the iscmerisation to (carboxylic) acids whi can be removed by means of ion exchangers.
Excellent results are also obtained with s ium chlorite as a coreagent besides the sodiu ydroxide required for the isomerisation, but a result of the formation of corrosive compound for example, chlorine and chlorodioxide, during the action, higher requirements are imposed on the appara s than when hydrogen peroxide is used.
Accord cg to a preferred embodiment of the method accord' g to the invention hydrogen peroxide is used as an o 'dant and is added after the basic isomerisation reaction a 0o o 00 00 0 0 0 0 0 00 00 oo o0 a 0 0 00 o 0o 00 o 0 0 0 o00 on 0 00 0000 0 0000.
Q1L Q4QRQ 0 -QQU4---- 15 It is recommendable in particular to add hydrogen peroxide, for example, in the form of 17.5% solution, to the isomerisation mixture at a temperature of approximately 50°C, after the pH of the mixture has become smaller than 7. However, it is also possible to add hydrogen peroxide at 20 a higher temperature of approximately 95°C under basic conditions (pH 7.5-8.0).
The reaction mixture, after isomerisation and treatment with H 2 0 2 or NaC102, is processed in the conventional manner. The non-converted lactose is removed 25 by crystallisation and is used again. The mixture comprising lactulose and decomposition products is purified by means of ion exchangers.
By using H 2 0 2 or NaC102 instead of Na 2
SO
3 NaHSO 3 and Na 3 P0 3 used so far, the decomposition products of lactulose which are formed during the isomerisation pre converted into readily decompcsable sugar carboxylic acids which cause no problems ecologically.
Z
1 0 a 4 0 o a a a i j.i r 14 3 DIR 0414 EXAMPLE I The data and results of a number of experiments on a laboratory scale are recorded in table A hereinafter. In all the experiments the isomerisation of lactose to lactulose was carried out with NaOH, optionally in the presence of Na 2
SO
3 The addition of H 2 0 2 according to the invention after the isomerisation reaction was carried out in two different manners: method I: in basic conditions (pH 7.5-8) at approx. ,10 method II: in acid conditions (pH at approx. 000000 0 0 0000 0 0 00 a Table A 00 00 o O 00 00 o 0 0 0 0 00 00 00 0000 0 0 0 0 o 0 0o ao 000 0 0 000 15 20 Exp. NaOH Na 2
SO
3
H
2 0 2 Method Colour after No. g/kg lactose.lH20 (ditto) (ditto) isomerisation 1 2.5 13-16 2 2.0 2.0 3-10 3 2.5 2.4 I 2-3 4 2.5 2.4 II 6-7 The colour is compared with the Gardner scale, a colour scale from 1 (colourless) to 20 (reddish brown).
On the basis of the colourindex the use of H 2 0 2 25 according to method I were to be preferred. On the basis of results of stability experiments (ageing tests), however, it seems that method II leads to a slightly better result.
EXAMPLE II The data and results of a number of experiments on a laboratory scale are recorded in table B. As in example I in all the experiments the isomerisation was carried out 4 DIR 0414 with NaOH, optionally in the presence of Na 2
SO
3 The addition of NaC1O 2 was carried out simultaneously with the addition of NaOH at about Table B Exp. Na0H Na 2 S0 3 NaClO 2 Colour after No. g/kg lactose.1H 2 0 (ditto) (ditto) isomerisation* 5 2.5 -13-16 6 2.0 2.0 -3-10 7 1.9 2 .7 3-8 8 3.5 -1.2 13-16 9 3 .5 3 3.9 3-8 00 0 0 t 000 0 o 0 00 '0 00 00 00 00 00 00'015 0000 0 0 Gardner scale 0 000 0 00 00 0 C, 00 0000 0 0 Ij 0 a0
Claims (5)
1. A method of preparing lactulose by basic isomerisation of lactose, wherein the reaction mixture is treated with hydrogen peroxide or sodium chlorite.
2. A method as claimed in claim 1, wherein 0.5-5 g of H202 is used per kg of
3. A method as claimed in claim 1 or claim 2 wherein H202 is added at a pH lower than 7.0, and at a temperature of approximately 50 0 C.
4. A method as claimed in claim 1 or claim 2 wherein H202 is added in basic conditions at pH 7.5-8.0 and at a temperature of approximately 95 0 C. A method as claimed in claim 1, wherein about 1.2 to about 3.9 g of NaC10 2 are used per kg of lactose. 1H 2 0 at a temperature of about 95 0 C and in basic conditions.
6. A method as claimed in claim 1 substantially as hereinbefore described with reference to any one of the o o examples. 0 0 0 a o0 o 0 o o a0 o° DATED: 7 February 1991 0 0 0 o 0 00 0 a PHILLIPS ORMONDE FITZPATRICK 0 0 Patent Attorneys for: DUPHAR INTERNATIONAL RESEARCH B.V. S CC o to6 o G 0 t 0 4\DMW/2320U ^Liy
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL8801102 | 1988-04-28 | ||
| NL8801102 | 1988-04-28 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU3339189A AU3339189A (en) | 1989-11-02 |
| AU609969B2 true AU609969B2 (en) | 1991-05-09 |
Family
ID=19852220
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU33391/89A Expired AU609969B2 (en) | 1988-04-28 | 1989-04-26 | Method of preparing lactulose |
Country Status (13)
| Country | Link |
|---|---|
| US (1) | US5026430A (en) |
| EP (1) | EP0339749B1 (en) |
| JP (1) | JP2675614B2 (en) |
| AT (1) | ATE113055T1 (en) |
| AU (1) | AU609969B2 (en) |
| CA (1) | CA1319933C (en) |
| DE (1) | DE68918887T2 (en) |
| DK (1) | DK170977B1 (en) |
| ES (1) | ES2061936T3 (en) |
| IE (1) | IE65054B1 (en) |
| IL (1) | IL90086A0 (en) |
| NZ (1) | NZ228900A (en) |
| ZA (1) | ZA893097B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3920288B2 (en) * | 2002-06-04 | 2007-05-30 | 森永乳業株式会社 | Method for producing lactulose-containing powder composition, lactulose-containing powder composition obtained by the method, and feed additive |
| RU2734782C1 (en) * | 2020-04-15 | 2020-10-23 | Общество с ограниченной ответственностью «Завод глубокой переработки молока «ЛактоПром» | Lactulose production method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4555271A (en) * | 1983-06-20 | 1985-11-26 | Sirac Spa | Process for purifying lactulose syrup |
| AU3145989A (en) * | 1988-03-18 | 1989-09-21 | Duphar International Research B.V. | Method of preparing solid lactulose |
| AU4716689A (en) * | 1988-12-21 | 1990-06-28 | Duphar International Research B.V. | Method of manufacturing lactulose |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT288595B (en) * | 1969-02-07 | 1971-03-10 | Laevosan Gmbh & Co Kg | Process for the production of lactulose concentrate |
| US4196017A (en) * | 1979-01-29 | 1980-04-01 | Holly Sugar Corporation | Method for reducing color impurities in sugar-containing syrups |
| US4536221A (en) * | 1982-12-17 | 1985-08-20 | Sirac Spa | Process for preparing lactulose from lactose, in the form of a syrup or a crystalline product |
-
1989
- 1989-04-25 IL IL90086A patent/IL90086A0/en unknown
- 1989-04-25 JP JP1103568A patent/JP2675614B2/en not_active Expired - Lifetime
- 1989-04-25 DK DK198989A patent/DK170977B1/en not_active IP Right Cessation
- 1989-04-25 CA CA000597673A patent/CA1319933C/en not_active Expired - Lifetime
- 1989-04-25 IE IE133189A patent/IE65054B1/en not_active IP Right Cessation
- 1989-04-26 AT AT89201072T patent/ATE113055T1/en not_active IP Right Cessation
- 1989-04-26 DE DE68918887T patent/DE68918887T2/en not_active Expired - Lifetime
- 1989-04-26 ZA ZA893097A patent/ZA893097B/en unknown
- 1989-04-26 ES ES89201072T patent/ES2061936T3/en not_active Expired - Lifetime
- 1989-04-26 EP EP89201072A patent/EP0339749B1/en not_active Expired - Lifetime
- 1989-04-26 AU AU33391/89A patent/AU609969B2/en not_active Expired
- 1989-04-26 NZ NZ228900A patent/NZ228900A/en unknown
-
1990
- 1990-08-13 US US07/566,314 patent/US5026430A/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4555271A (en) * | 1983-06-20 | 1985-11-26 | Sirac Spa | Process for purifying lactulose syrup |
| AU3145989A (en) * | 1988-03-18 | 1989-09-21 | Duphar International Research B.V. | Method of preparing solid lactulose |
| AU4716689A (en) * | 1988-12-21 | 1990-06-28 | Duphar International Research B.V. | Method of manufacturing lactulose |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01313490A (en) | 1989-12-18 |
| ATE113055T1 (en) | 1994-11-15 |
| IL90086A0 (en) | 1989-12-15 |
| DK198989D0 (en) | 1989-04-25 |
| DE68918887T2 (en) | 1995-02-23 |
| IE65054B1 (en) | 1995-10-04 |
| DK198989A (en) | 1989-10-29 |
| AU3339189A (en) | 1989-11-02 |
| CA1319933C (en) | 1993-07-06 |
| ES2061936T3 (en) | 1994-12-16 |
| ZA893097B (en) | 1990-01-31 |
| DK170977B1 (en) | 1996-04-09 |
| NZ228900A (en) | 1990-12-21 |
| EP0339749A1 (en) | 1989-11-02 |
| EP0339749B1 (en) | 1994-10-19 |
| JP2675614B2 (en) | 1997-11-12 |
| US5026430A (en) | 1991-06-25 |
| DE68918887D1 (en) | 1994-11-24 |
| IE891331L (en) | 1989-10-28 |
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